7 tablespoons (100 g) unsalted butter, divided
8 oz. (225 g) semi-sweet chocolate chips
1/2 cup (110 g) brown sugar
1/4 cup (50 g) granulated sugar
1 teaspoon (5 g) vanilla extract
1/2 cup corn starch
3 tablespoons (21 g) unsweetened cocoa powder
1/4 teaspoon (2 g) salt
Place chocolate chips and 6 tablespoons of butter in a bowl and heat them in the microwave until completely melted and combined, stopping and stirring every 30 seconds.
In the same bowl, add in granulated sugar, eggs, and vanilla. Mix well with a whisk. Add brown sugar.
Sift together corn starch, cocoa powder, and salt. Fold into chocolate mixture and mix well.
Grease the inside of a 6-quart slow cooker with remaining tablespoon of butter. Transfer the brownie mix to the slow cooker.
Place a few paper towels over the top of the slow cooker to absorb moisture, then cover and cook for 2 hours on high.
Remove pot from base. Allow brownies to cool for 10 minutes with no lid before cutting and serving.
Tip: Customize these brownies by sprinkling a handful of chocolate chips, walnuts, or another favorite topping over batter before cooking.
Source : allrecipes.com